Top influencers can be identified universally by combining classical centralities

Information flow, opinion, and epidemics spread over structured networks. When using node centrality indicators to predict which nodes will be among the top influencers or superspreaders, no single centrality is a consistently good ranker across networks. We show that statistical classifiers using two or more centralities are instead consistently predictive over many diverse, static real-world topologies. Certain pairs of centralities cooperate particularly well in drawing the statistical boundary between the superspreaders and the rest: a local centrality measuring the size of a node’s neighbourhood gains from the addition of a global centrality such as the eigenvector centrality, closeness, or the core number. Intuitively, this is because a local centrality may rank highly nodes which are located in locally dense, but globally peripheral regions of the network. The additional global centrality indicator guides the prediction towards more central regions. The superspreaders usually jointly maximise the values of both centralities. As a result of the interplay between centrality indicators, training classifiers with seven classical indicators leads to a nearly maximum average precision function (0.995) across the networks in this study.

Расчет нормальных температурных напряжений в компонентах асфальтобетона методами статистической механики композитов

Учет температурных напряжений важен при выполнении расчетов на прочность дорожного покрытия. В данной статье приводятся результаты исследования распределения нормальных температурных напряжений для компонент асфальтобетона. Показано логарифмически нормальное распределение нормальных температурных напряжений для включения и распределение Гаусса для нормальных температурных напряжений связующего. Исследование проведено с применением теоретических методов статистической механики композитов, аналитических методов решения статистической краевой задачи механики композитов, математического моделирования, методов программирования в математическом пакете MathCad. Ключевые слова: асфальтобетон, температурные напряжения, статистическая краевая задача механики композитов, математическое моделирование, пакет программ. Consideration of temperature stresses is important when performing calculations of road surface strength. The results of study of the distribution of temperature stresses components for asphalt concrete are given herein. Lognormal distribution of components of thermal stresses for inclusion and normal distribution of components for thermal stresses of thebinding agent are shown. The study was carried out using theoretical methods of mechanics of composites, analytical methods for solving the statistical boundary value problem of mechanics of composites, numerical and experimental modelling, programming methods in the mathematical package MathCad. Keywords: asphalt concrete, temperature stresses, statistical boundary value problem, mechanics of composites, numerical experiment, laboratory experiment.

Ecohydraulogical Characteristic Index System of Schizopygopsis younghusbandi during Spawning Periods in the Yarlung Tsangpo River

To address the species decline in aboriginal fish in the Yarlung Tsangpo River Basin and the lack of research on the habitat characteristics of fish spawning grounds, this paper studied the changing trends in runoff in spawning grounds and the habitat conditions characteristics of Schizopygopsis younghusbandi during the spawning period. In conventional approaches, inaccurate statistical results are obtained when a full river section is taken as the region to be assessed, so a new method for determining the statistical boundaries of characteristic indexes was proposed. By combining hydrological analyses, mathematical statistics, and numerical simulations, the statistical boundary of the index was determined, and a suitable range for the habitat characteristic indexes for the spawning field was finally obtained. The results showed that (1) the maximum percentage of the statistical boundary for the spawning grounds was 39% near the banks on both sides of the river; (2) the flow during the spawning period exhibited small variations, a short duration and a fluctuation cycle and was dominated by water rising events, and the interannual growth trend in the daily flow was obvious; and (3) during the spawning period, the flow velocity of the fish habitat was small, the turbulence level of the fluid was low, and the flow regime was stable. A suitable range for the habitat characteristic index of the target fish provided the basic data for the protection of aboriginal fish and was beneficial to maintain the balance of aquatic ecological system in the Yarlung Tsangpo River. The results of this study contribute to the rational development of water resources in the basin and the protection of species diversity and water environment.

A Method to Evaluate Low Voltage Supply System’s Reliability

The low voltage supply system’s reliability play an important role on improving equipment’s operation level and standards of management, this paper proposed a method to evaluate the reliability of low voltage supply system .The method was composed of four parts: statistical index system, definition of every index’s meaning and statistical formulas, confirming the statistical boundary conditions. In order to test the effective and practicability of the method, this paper evaluated the low voltage power supply’s reliability of BinZhou and the results are satisfactory.